Question

A student calculated there to be 0.002395 mol Cu2+ ions in one 25.00 mL titration sample. Calculate how many moles of Cu2+ ions were present in the 250.0 mL volumetric flask before the three 25.00 mL samples were removed?

A student calculated there to be 0.002395 mol Cu2+ ions in one 25.00 mL titration sample. Calculate how many moles of Cu2+ ions were present in the 250.0 mL volumetric flask before the three 25.00 mL samples were removed.

Answer 1

Would there not be 10 EQUIV...

Explanation:

You took a `25.00*mL` aliquot of a `250*mL` solution. In the aliquot there were `2.395*mmol`...and so there were TEN TIMES this molar quantity in `250*mL`..

And thus `[Cu^(2+)]=(10xx2.395xx10^-3*mol)/(250*mLxx10^-3*L*mL^-1)=0.09580*mol*L^-1`...with respect to cupric ion...